Answer:
532
Step-by-step explanation:
The score that represents the top 20% = A score = 80%
Z score for 80% percentile = 0.842
We solve using the z score formula
z = (x-μ)/σ, where
x is the raw score = ??
μ is the population mean = 490
and σ is the population standard deviation = 50
Hence:
0.842 = x - 490/50
Cross Multiply
0.842 × 50 = x - 490
x = 0.842 × 50 + 490
x = 42.1 + 490
x = 532.1
Approximately = 532
Therefore, the test score = 532
(0,50)(5,100)
slope = (100 - 50) / 5 - 0) = 50/5 = 10
y = mx + b
slope(m) = 10
(0,50)...x = 0 and y = 50
now we sub and find b, the y int
50 = 10(0) + b
50 = b
equation is : y = 10x + 50
Angel has 50 and she saves 10 a week <===
